The present disclosure relates to a toner case that contains toner, an image forming apparatus equipped with the toner case, and a method of driving a toner case.
Today, in electrophotographic image forming apparatuses, toner is supplied from a developing unit to an electrostatic latent image formed on the surface of a photoconductor drum, or the like, to perform a developing process. Toner used in such a developing process is supplied to the developing unit from a toner case.
For example, a toner case equipped with a toner container that contains toner and an intermediate hopper is known. The intermediate hopper is mounted between the toner container and the developing unit. The above-described intermediate hopper is typically provided with an agitating unit such as an agitating paddle and a transportation unit such as a transportation screw. The agitating unit agitates the toner and the transportation unit transports the toner. The intermediate hopper allows the toner transported from the toner container, to be transported to the developing unit using the transportation unit while the toner is agitated using the agitating unit. With the intermediate hopper having the above-described structure being located between the toner container and the developing unit, the toner can be supplied to the developing unit from the intermediate hopper even when the toner container runs out of toner. This allows the toner container to be replaced without a delay in the supply of toner to the developing unit.
In the related art intermediate hopper having the above-described structure, in order to meet the demands for a reduction in the size of the apparatus and the like, the agitating unit and the transportation unit are rotated using a single driving unit (for example, a motor). That is, when the agitating unit is rotated by the driving unit, the transportation unit is always simultaneously rotated along with the agitating unit.
In a toner case having the above-described structure, sometimes it is desirable that only an agitation of the toner contained in the intermediate hopper is performed. Such a situation occurs, for example, immediately after the mode of the image forming apparatus has been changed from a sleep mode to a normal mode, after the power has been turned on, after the toner container has been replaced, and the like. In addition, in order to quickly and correctly detect the remaining amount of the toner in the intermediate hopper, the toner contained in the intermediate hopper needs to be agitated even when toner is not being transported from the intermediate hopper to the developing unit. However, as described above, in the related art intermediate hopper, when the agitating unit is rotated, the transportation unit is always simultaneously rotated. Thus, operation of the intermediate hopper wherein the intermediate hopper agitates the toner without supplying the toner from the intermediate hopper to the developing unit cannot be performed.